Fuel injectors routinely use pistons (sometimes referred to as intensifier pistons) that operatively communicate with injection rate shaping orifices. The part of the fuel injector assembly, such as a fuel injector body, which defines such an injection rate shaping orifice may be subject to erosion or damage for a host of reasons. For example, a valve member of the fuel injector may impact the area of the injection rate shaping orifice or dirty hydraulic oil may act at the surface defining the injection rate shaping orifice at a high pressure. This may create cavitation that causes this area to wear. As a result of either scenario, the dimensions associated with the injection rate shaping orifice may change to the point where these dimensions are out of tolerance. Of course, there is an associated detriment to the intended performance of the injection rate shaping orifice at this point.
Once this situation is determined to exist, the fuel injector as a whole or the fuel injector body may need to be replaced. However, replacing the fuel injector as a whole or even just the fuel injector body may be time consuming and costly. Furthermore, in some instances, it may be desirable to alter the original geometry of the injection rate shaping orifice for various reasons such as to improve fuel economy, reduce emissions or for various other performance related reasons.
Accordingly, it is desirable to develop a method and apparatus that may allow the user of a fuel injector to remanufacture, refurbish or otherwise replace the injection rate shaping orifice of a fuel injector in a reliable and economic manner.